Development of the cavernous sinus in the fetal period: a morphological study

Anatomical Basis of Clinical Manifestations Seen in Cavernous Sinus Syndrome: A Narrative Review

Pathology involving the Cavernous Sinus (CS), generally referred to as Cavernous Sinus Syndrome (CSS), can arise from vascular disorders, neoplasms, infections, and non-infectious inflammatory disorders. An acute understanding of the CS and its regional anatomical structures is therefore pertinent in expounding the highly variable clinical manifestations seen in CSS as well as laying the groundwork for surgical intervention. Though the neuroanatomy of the cavernous sinus has been substantially chronicled in literature, their correlation to clinical signs has only been minimally described. This narrative review serves to address this knowledge gap and aims to comprehensively correlate the clinical manifestations of CSS with the relevant neuroanatomy, thereby allowing medical practitioners to better navigate the diagnostic quandary. We conducted a scoping review of the literature concerning CS anatomy and CSS, complied through MEDLINE/OVID and cross-referencing of articles on PubMed and Google Scholar with the keywords cavernous sinus, cavernous sinus syndrome, clinical signs/manifestations, neuroanatomy, CS pathology, Cavernous Sinus Thrombus (CST) and cavernous sinus neoplasms/tumours.

Embryology of the Cavernous Sinus and Relevant Veins

The cavernous sinus (CS) is a parasellar dural envelope containing an important venous pathway. The venous channels, which have an endothelial layer and no smooth muscle layer, are located in connective tissue. In the early embryonic stages, the neural tube is surrounded by the primitive capillary plexus and undifferentiated mesenchymal tissue, the primary meninx, and initially drains into the primary head sinus (PHS) through the anterior, middle, and posterior dural plexus (ADP, MDP, and PDP). Subsequently, following enlargement of the brain and differentiation of the mesenchyme, two major primary sinuses, the pro-otic sinus and the primitive tentorial sinus, become prominent. The pro-otic sinus is the remnant of the short segment of the PHS cranial to the MDP and the stem of the MDP. The CS originates from the plexiform channels medial to the trigeminal ganglion, namely the medial tributaries of the pro-otic sinus. The stem of the pia-arachnoidal vein draining into the ADP represents the primitive tentorial sinus. It is considerably elongated due to expansion of the cerebral hemisphere, and migrates medially toward the CS. The morphological changes in the CS and primitive tentorial sinus exhibit considerable variation in cerebral venous drainage patterns. Embryological knowledge facilitates interpretation of the anatomy of the CS, and it is useful to perform safe and beneficial endovascular treatment for the CS.

Revisit the Cavernous Sinus from Fetus to Adult-New and Old Data

This article highlighted three advances in the study of the cavernous sinus: (1) the initial formation of the sinus reticulum in early development of the sphenoid bone before ossification (2) extension of reticulum of the sinus and connection with other venules, and (3) the cavernous sinus and the nerves evolved inside this sinus during gestation, for example, the trigeminal nerve already formed bundles of motor and parasympathetic components during fetal development. This ontogenetic study further confirmed the cavernous sinus is not a single or a dual set of sinuses, but a group of extensions of venous sinuses or sinusoids. These new insights were integrated with previous understandings of the cavernous sinus to form this review article. Anat Rec, 301:819-824, 2018. © 2017 Wiley Periodicals, Inc.

Dural Venous System in the Cavernous Sinus: A Literature Review and Embryological, Functional, and Endovascular Clinical Considerations

The cavernous sinus (CS) is one of the cranial dural venous sinuses. It differs from other dural sinuses due to its many afferent and efferent venous connections with adjacent structures. It is important to know well about its complex venous anatomy to conduct safe and effective endovascular interventions for the CS. Thus, we reviewed previous literatures concerning the morphological and functional venous anatomy and the embryology of the CS. The CS is a complex of venous channels from embryologically different origins. These venous channels have more or less retained their distinct original roles of venous drainage, even after alterations through the embryological developmental process, and can be categorized into three longitudinal venous axes based on their topological and functional features. Venous channels medial to the internal carotid artery "medial venous axis" carry venous drainage from the skull base, chondrocranium and the hypophysis, with no direct participation in cerebral drainage. Venous channels lateral to the cranial nerves "lateral venous axis" are exclusively for cerebral venous drainage. Venous channels between the internal carotid artery and cranial nerves "intermediate venous axis" contribute to all the venous drainage from adjacent structures, directly from the orbit and membranous skull, indirectly through medial and lateral venous axes from the chondrocranium, the hypophysis, and the brain. This concept of longitudinal venous axes in the CS may be useful during endovascular interventions for the CS considering our better understandings of its functions in venous drainage.

Histological structure of the medial and lateral walls of cavernous sinus in human fetuses

PURPOSE

The aim of this study is to elucidate the architecture of these fine structures in human fetuses.

METHODS

The histological examination of medial wall (MW) and lateral wall (LW) was performed in 15 normal human fetuses. Eleven fetuses were female and four were male. The gestational age ranged between 14 and 35 weeks. The weight ranged between 180 and 1750 g. The wall samples (two MW and two LW from each fetus) were obtained by microsurgical technique and underwent histological examination. Each wall was examined for the structure and composition of collagen and elastic fibers, ganglions, peripheral nerves, and vessels.

RESULTS

A total of 60 wall samples (30 MW and 30 LW) were examined in 15 fetuses. Loose connective tissue composed of type III collagen was observed in both of the walls. Elastic fibers were observed only in three wall samples (two MW and one LW). Ganglion was detected in 11 samples (nine in LW and two in MW), and peripheral nerve was found in 28 walls (18 LW and 10 MW). Vessels were observed in 51 samples (26 LW and 25 MW). None of the walls was stained with type I collagen.

CONCLUSIONS

The structure of LW and MW of the cavernous sinus (CS) in fetuses is mainly composed of collagen tissue while some elastic fibers are supported by this tissue. Type III collagen is the main component of fetal CS walls. Because of the weak histological structure, CS may be more prone to tumor invasion in infants.

Endovascular treatment of carotid-cavernous fistulas

Endovascular management has become the treatment of choice for carotid-cavernous fistulas regardless of the fistula type. The endovascular method offers numerous options that render it capable of treating each fistula type by choosing an adequate technique. This advantage along with the advancement in the field has led to fewer complications with higher success rate.

Carotid-cavernous fistulas

Carotid-cavernous fistulas (CCFs) are vascular shunts allowing blood to flow from the carotid artery into the cavernous sinus. The characteristic clinical features seen in patients with CCFs are the sequelae of hemodynamic dysfunction within the cavernous sinus. Once routinely treated with open surgical procedures, including carotid ligation or trapping and cavernous sinus exploration, endovascular therapy is now the treatment modality of choice in many cases. The authors provide a review of CCFs, detailing the current classification and clinical management of these lesions. Therapeutic options including conservative management, open surgery, endovascular intervention, and radiosurgical therapy are presented. The complications and treatment results as reported in the contemporary literature are also reviewed.

Embryology of the internal carotid artery dural crossing: apropos of a continuous series of 48 specimens

The aim of this study was to describe the embryologic and foetal development of the anterior paraclinoid region and more precisely the relationship of the internal carotid artery to the dura mater. This has been done by examining a collection of histological sections, representing a continuous series of 48 embryologic and foetal specimens, covering the period of the first 6 months of intra-uterine life. Neurological and vascular elements develop during the embryologic period; the internal carotid artery is recognizable in the various sections of its course and acquires a histological adult parietal constitution. The foetal period corresponds to the development of the meningeal structures. The superior, medial and lateral walls appear on the fifteenth week of amenorrhoea and do not change after that. The internal carotid artery enters subarachnoid space accompanied by a sleeve of mesenchymatous cells, which fixes it to the anterior clinoid process. The constitution of this sleeve, arising from the superior wall of the lateral sellar compartment, remained independent of the principle vascular part, which allows the formation of a plan of cleavage. The foetal relations of the dura mater and the internal carotid artery were seen to be different from those of adult subjects described in the literature, suggesting an existence of period of maturation postnatally.

Intratumoral injection of plastic adhesive material for removal of cavernous sinus hemangioma. Technical note

The authors present a case in which a cavernous sinus (CS) hemangioma was totally removed following intratumoral injection of a plastic fixation material. This unique method is extremely useful for the removal of CS hemangiomas, which often feature massive intraoperative bleeding as an unsolved problem.